Seasonic's S12G-550; you have to pay for prime power

With an 80 Plus Gold rating and the ability to deliver 45A on its single 12V rail the 550W Seasonic S12G-550 PSU is perfect for a mid-range rig. A pair of 6+2 PCIe connectors gives you a choice of powering a single high end GPU or two low or midrange GPUs. It is also relatively small, barely larger than the 120mm cooling fan it uses though some may be turned off by its non-modular cables. At around $85 it is not the least expensive model at that wattage but [H]ard|OCP's Silver Award proves it is worth it if you want solid power for your system.

"Seasonic builds some of the best computer power supplies on the market. When do we ever get a power supply that is actually a better product than what it is marketed to be? Not often, but that is the case with the S12G-550 PSU. It is not terribly inexpensive, but it is a great value for your hard earned dollars."